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941.
Richard K. Haynes Burkhard Fugmann Jrg Stetter Karl Rieckmann Hans‐Dietrich Heilmann Ho‐Wai Chan Man‐Ki Cheung Wai‐Lun Lam Ho‐Ning Wong Simon L. Croft Livia Vivas Lauren Rattray Lindsay Stewart Wallace Peters Brian L. Robinson Michael D. Edstein Barbara Kotecka Dennis E. Kyle Bernhard Beckermann Michael Gerisch Martin Radtke Gabriele Schmuck Wolfram Steinke Ute Wollborn Karl Schmeer Axel Rmer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2006,118(13):2136-2142
942.
943.
Hans‐Dietrich Stachel Eduard Eckl Elisabeth Immerz‐Winkler Christine Kreiner Wolfgang Weigand Christian Robl Ralf Wünsch Stefan Dick Norbert Drescher 《Helvetica chimica acta》2002,85(12):4453-4467
The title compounds were prepared starting from pyrrolinone 4 . Nucleophilic‐displacement and ring‐closure reactions yielded the dithiolopyrrole 5a , which formed salts with electrophiles ( 7, 8 ) as well as with bases. The crystal structure of 5a was determined. Oxidation of the dithioles 5a and 6a led to S(2)‐oxides ( 10a, 11a ) and the corresponding S(2)‐dioxides ( 10b, 11b ) depending on reaction conditions. The thiosulfinate 10a was converted by a ring‐opening/ring‐closure reaction sequence to the bicyclic sulfinamide 12 . The oxidative addition reactions of [Pt(η2‐C2H4) (PPh3)2] ( 14 ) with the disulfides 5a and 13 led to the dithiolatoplatinum(II) complexes 15 and 16 , respectively. Complex 16 was characterized structurally. The sulfenato‐thiolato complex 17 was synthesized via reaction of 14 with the thiosulfinate 10a . The thiosulfonato PtII complex 18 was prepared by an oxidative insertion of Pt0 into the C? S bond of the corresponding thiosulfonate 10b . Furthermore, complex 18 was characterized by single‐crystal X‐ray‐diffraction studies. 相似文献
944.
L. Schweikhard P. Beiersdorfer W. Bell G. Dietrich S. Krückeberg K. Lützenkirchen B. Obst J. Ziegler 《Hyperfine Interactions》1996,99(1):97-104
Singly charged gold cluster ions from a laser-vaporization source are transferred into a Penning trap and subjected to electron bombardment. The charged reaction products are analyzed by time-of-flight mass spectrometry after axial ejection from the trap. They include singly charged cluster fragments, multiply charged clusters of the initial size and multiply charged cluster fragments. The multiply charged clusters are selected and further investigated by collision induced dissociation. Two types of reactions can be distinguished: Dissociation into several charged fragments and evaporation of neutrals. Several features of multiply charged clusters relevant for future investigations are reviewed.This work comprises part of the dissertation of J. Ziegler. 相似文献
945.
946.
947.
The daily financial volume of transaction on the New York Stock Exchange and its day-to-day fluctuations are analysed with respect to power-law tails as well to their long-term trends. We also model the transition to a Gaussian distribution for longer time intervals, like months instead of days. 相似文献
948.
Damage spreading for Ising cluster dynamics is investigated numerically by using random numbers in a way that conforms with the notion of submitting the two evolving replicas to the same thermal noise. Two damage spreading transitions are found; damage does not spread either at low or high temperatures. We determine some critical exponents at the high-temperature transition point, which seem consistent with directed percolation. 相似文献
949.
R. J. Tonucci D. H. Pearson D. S. Katzer A. Rosenberg H. B. Dietrich 《Superlattices and Microstructures》1996,20(4):627-632
Nanochannel glass replica films have been used as masks for thein-situparallel patterning of GaAs/AlGaAs single quantum wells during growth by MBE. Quantum well pyramids with lateral dimensions as small as 500 nm exhibit low temperature (5 K) photoluminescence associated with the 50 Å well thickness of the structure. By control of the replica membrane properties and deposition conditions, we demonstrate that it may be possible to reduce the lateral dimensions of layered structures beyond what would normally be expected from the starting apertures. 相似文献
950.
J. Ziegler G. Dietrich S. Krückeberg K. Lützenkirchen L. Schweikhard C. Walther 《Hyperfine Interactions》1998,115(1-4):171-179
Collision induced dissociation is applied to study the fragmentation channels of multiply charged gold clusters, Au N2+, size N= 7 –35, and Au>
N3+}, N = 19–35, stored in an ion cyclotron resonance (Penning) trap. The main dissociation pathways are neutral monomer evaporation,
Au>
NZ+to Au>
N-1Z+} + Au, for the larger and fission into a charged trimer plus the remaining cluster, Au>
NZ+to{}Au>
N-3(Z-1)+} +{}Au>
3+}, for the smaller clusters. In the intermediate cluster size region an odd–even alternation of the two competing decay pathways
is observed. In addition, for some specific cluster sizes there are indications of neutral dimer evaporation, Au>
NZ+to{}Au>
N-2Z++Au>
2}, and of extremely asymmetric fission of the form Au>
NZ+to Au>
N-1(Z-1)+} + Au+.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献